FieldItemInterface

class \Drupal\Core\Field\FieldItemBase implements \Drupal\Core\Field\FieldItemInterface extends \Drupal\Core\TypedData\Plugin\DataType\Map
class \Drupal\Core\Field\Plugin\Field\FieldType\BooleanItem implements \Drupal\Core\TypedData\OptionsProviderInterface extends \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\ChangedItem extends \Drupal\Core\Field\Plugin\Field\FieldType\CreatedItem
class \Drupal\Core\Field\Plugin\Field\FieldType\CreatedItem extends \Drupal\Core\Field\Plugin\Field\FieldType\TimestampItem
class \Drupal\Core\Field\Plugin\Field\FieldType\DecimalItem extends \Drupal\Core\Field\Plugin\Field\FieldType\NumericItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\EmailItem extends \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem implements \Drupal\Core\TypedData\OptionsProviderInterface, \Drupal\Core\Field\PreconfiguredFieldUiOptionsInterface extends \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\FloatItem extends \Drupal\Core\Field\Plugin\Field\FieldType\NumericItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\IntegerItem extends \Drupal\Core\Field\Plugin\Field\FieldType\NumericItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\LanguageItem implements \Drupal\Core\TypedData\OptionsProviderInterface extends \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\MapItem extends \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\NumericItemBase extends \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\PasswordItem extends \Drupal\Core\Field\Plugin\Field\FieldType\StringItem
class \Drupal\Core\Field\Plugin\Field\FieldType\StringItem extends \Drupal\Core\Field\Plugin\Field\FieldType\StringItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\StringItemBase extends \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\StringLongItem extends \Drupal\Core\Field\Plugin\Field\FieldType\StringItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\TimestampItem extends \Drupal\Core\Field\FieldItemBase
class \Drupal\Core\Field\Plugin\Field\FieldType\UriItem extends \Drupal\Core\Field\Plugin\Field\FieldType\StringItem
class \Drupal\Core\Field\Plugin\Field\FieldType\UuidItem extends \Drupal\Core\Field\Plugin\Field\FieldType\StringItem
class \Drupal\field_example\Plugin\Field\FieldType\RgbItem extends \Drupal\Core\Field\FieldItemBase
class \Drupal\field_permission_example\Plugin\Field\FieldType\FieldNote extends \Drupal\Core\Field\FieldItemBase

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